Millions of women know Cynthia Nixon as blunt lawyer Miranda Hobbs on HBO’s hit series – and its two feature films – “Sex and the City.” But she’s more than just Miranda: The actress has survived breast cancer. In this Lifescript exclusive, Nixon opens up about her battle with breast cancer and how she measures up to her on-screen alter ego…

It’s been two years since the first “Sex and the City” broke records – $55.7 million in its opening weekend (the biggest opening ever for a romantic comedy), and worldwide box office sales of more than $400 million – and it’s clear fans still can’t get enough of Carrie, Charlotte, Samantha and Miranda.

The Manhattan gals are back in a sequel, in theaters now, with their wardrobes and friendships intact, but facing a new set of problems.

Picking up two years after the first film, the women are all at a point of transition in their lives: Carrie and Big are having marital issues, Samantha is facing menopause, Charlotte is struggling with motherhood, and Miranda is unhappy with her job.

Like Miranda, Nixon, 44, has experienced her own personal upheavals the past few years.

Nixon was diagnosed with breast cancer four years ago, at age 40, following a routine mammogram. She started getting mammograms regularly at age 35 because her mother, Anne, is a two-time breast cancer survivor who was first diagnosed 30 years ago.

At that time, Nixon’s mother took her diagnosis in stride, looking at it as a solvable problem. She has passed on that positive approach to her daughter.

"When I got my breast cancer diagnosis, I had an experience very similar to my mother's, although I have to say that the science is much better now," says Nixon, who had a cancerous lump and one of her lymph nodes removed during her surgery.

Fortunately, she didn't need chemotherapy, but she did undergo 6-1/2 weeks of radiation treatment.

So “SATC” star chose to educate others: She became an ambassador for Susan G. Komen for the Cure, the world’s largest breast cancer organization, and filmed a public service announcement for Stand Up to Cancer about how to minimize infection risk during cancer treatment.

"One of my main reasons for getting involved is I have a very concrete story to tell," Nixon says. "And I feel like it’s a very useful story. It isn't just my story. It is my mother's and my story, which is to be proactive – get your mammograms. Don't be afraid.

"Luckily, because of Susan G. Komen and all the medical advances in the past 25-plus years, this is a really [manageable] disease if you catch it in time. The worst thing you can do is to be too afraid to check it out."

In the film adaptation of the first “SATC,” Miranda dealt with a betrayal by her husband; fortunately, Nixon’s real love life is far happier.

In 2003, Nixon ended her 15-year relationship with Danny Mozes, the father of her two children − daughter, Samantha, 15, and son, Charlie, 8 − and fell in love with a woman, education activist Christine Marinoni.

It was a relationship that caught many off guard, including her. Discussing it on "The Oprah Winfrey Show," Nixon admitted, "I was pretty shocked. I have to tell you."

But being in a lesbian relationship has made Nixon more aware of the needs of the gay community, especially when it comes to women and breast cancer.

"Gay women face unique challenges when it comes to breast cancer,” Nixon says. “Since we’re not as focused on birth control and reproductive issues, we tend to visit the gynecologist less often than straight women do.”

That means they might not get early detection tests like mammograms and clinical breast exams.

So breast cancer may not be detected in its earliest, most treatable stages, she says.

Even though Nixon had a lumpectomy in 2006, she still agreed to a nude scene in the first “SATC” film.

"I was a little nervous about it," admits the actress. "I didn't feel so naked because David Eigenberg [who plays her husband, Steve] was really protecting me and covering me, and my makeup people were making me look good. [Writer/director] Michael Patrick [King] was working on the cameras, so I felt pretty taken care of."

The question that inevitably comes up from fans is: How similar is Nixon to Miranda?

"Miranda does the zingers and [so] do I in real life, but Miranda's whole rhythm and tone is very different than mine," Nixon says.

"She's much more likely to put people on the spot,” Nixon says. “I'm the first person in line to let somebody off the hook.”

Miranda is also less glamorous than the rest of the girls, but more realistic and relatable to women, she says.

Another difference: Nixon is not a real redhead. A natural blonde, Nixon dyes her hair for the role, which she admits helps her get into character − that and the clothes.

Ah, those clothes. The fabulous fashions worn by the ladies of “SATC” are as much a hallmark of the show as the foursome’s romantic ups and downs. And while Miranda’s style isn’t as avant-garde as Carrie’s, she certainly is a fashionista.

In contrast, Nixon claims the only time she was really in style was during the ’90s grunge era.

"Luckily, I've inherited all these great clothes, and designers have given me great clothes, so it’s now not so hard, because I have this closet full of beautiful clothes," she says. "But it’s really one of the last things I think about."

Running around Manhattan in sky-high heels is also not a habit, unless she’s attending a celebrity event where she'll be photographed.

"Because I have all these high heels in the closet, I wear them periodically - the way you would go to the gym - so I don't lose that muscle," she says.

The success of the first “SATC” movie allowed Nixon to take on less commercial films, such as Lymelife with Alec Baldwin and Timothy Hutton, which aired at film festivals, including Sundance, and in limited release in 2009.

It has also given her the freedom to continue with her stage work.

Nixon made her Broadway debut in 1980, starring in a revival of “The Philadelphia Story."

She has also balanced her TV and movie jobs with a steady stream of theater roles, even winning a Tony Award for Best Actress in a Leading Role in 2006 for her part in the Pulitzer Prize-winning play “Rabbit Hole.”

So how does the successful actress, mom and activist stay so grounded?

"Every decision that I make now, I really want to make it consciously and choose it − not just say, 'This looks good. I will take this job,'" Nixon says.

"It's about breathing and deciding and exploring and having fun and not always being so nose-to-the-grindstone."

Check out Nixon in the "SATC" sequel, in theaters now.

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